The present invention relates to industrial control systems generally, and in particular relates to a method and apparatus for mounting a human-machine interface onto a panel.
An automated manufacturing assembly typically includes a set of mechanical and electrical components, a controller and an interface device (e.g., a human-machine interface (HMI)). The mechanical and electrical components are integrated together to perform an automated manufacturing process. The controller is linked to a sub-set of the components (e.g., sensors) for receiving information regarding progression of the process and to another sub-set of the components (e.g., motors, actuators, etc.) for controlling progression of the process. The interface is typically linked to the controller to facilitate at least one of altering the process (i.e., altering process parameters) or monitoring the process. In particular, the interface generally includes an output terminal (such as a display) that provides data to the user that is relevant to the controlled process. Likewise, one or more inputs are typically provided that a user can engage to transmit information over the network to, for instance, the controller or controlled device.
While many different types of communication systems have been developed for linking the controller to the assembly components and to the interface, one particularly useful type of linkage is a network communication system, the Ethernet being an example. In the case of the Ethernet, for instance, an interface generates messages earmarked for the controller and transmits those messages onto the network. The controller listens on the network for messages earmarked for the controller and uses those messages to perform specific functions. Similarly, the controller earmarks specific messages for the interface and transmits those messages to the interface via the network.
Interfaces are typically mounted onto a panel having a front surface that faces the operator, and a rear surface that is generally inaccessible during normal operation. An opening is provided in the panel that receives the interface from the front. The interface is thus fastened to the panel at the rear panel surface. When mounting the interface, the rear of the panel is difficult to access and not visible by the user when stationed in front of the panel. In some instances, the rear panel surface can be accessed by the user. However, accessing the rear panel surface in order to mount an interface can be tedious and time-consuming, especially when mounting a plurality of interfaces onto a panel.
Accordingly, conventional mounting assemblies enable a user stationed in front of the panel to mount the interface on a blind rear panel surface. For instance, one typical mounting assembly includes a screw or other rotatable fastener that extends inwardly from the rear of the interface towards the rear surface of the panel that can be rotated until the fastener abuts the rear panel surface. Such fasteners must first be positioned in a threaded aperture, and are further ergonomically unfriendly to the user. Furthermore, when the fastener is rotated by the user, the fasteners will likely be blind to the user who is stationed at the front of the panel. As a result, under-rotation can compromise the mounting stability, while over-rotation can place excessive stresses on the fastening parts which can wear and fail over time.
What is therefore needed is a method and apparatus that facilitates mounting a HMI onto a panel in a less tedious and more reliable manner than conventionally achieved.